1. Field of the Invention
The invention relates to a backlight module, and more particularly, to the arrangement of lamps in the backlight module.
2. Description of the Related Art
FIG. 1 is a schematic view of a conventional backlight module. FIG. 2 is a sectional drawing of a conventional backlight module. Referring to FIGS. 1 and 2, a conventional backlight module 10 comprises a substrate 11, a plurality of lamps 12 and a plurality of lamp holders 13. Distances between each lamp 12 and the substrate 11 are equal. In other word, each lamp 12 is parallel to the substrate 11. The lamp holders 13 are installed on the substrate 11 for holding the lamps 12. The backlight module 10 further comprises a chamber 14 for sealing the lamps 12 and the lamp holders 13.
Referring to FIG. 2, when using the backlight module 10, the backlight module 10 stands. Thus, air surrounding the lamps 12 is heated and due to the decreasing density of the backlight module that would cause the air to move upward. During steady state operation, the backlight module 10, the upper portion of the chamber 14 fills with hot air. As a result, the temperature of the chamber 14 is not uniform. The temperature of the chamber 14 affects lamp efficiency and extinction ratio of liquid crystals. Due to the temperature of the backlight module 10 is not uniform, the lamp efficiency and the extinction ratio of liquid crystals will decrease and diminish the display efficiency.